The present invention relates to the field of constructions and systems designed to thermally insulate and seal a safing slot area defined between a curtain wall and the individual floors of a building. In particular, the present invention relates to a thermal insulating and sealing means for use with curtain wall structures which include an interior panel such as a back pan or other similar construction which can be of metal or other material extending across the interior surface of a curtain wall which is common in modular designs. The interior panels of a curtain wall are generally made from a metal or insulation material which can easily bend, distort or be otherwise deformed when exposed to strong winds or elevated temperatures, such as intensive sunlight or heat, such as in the event of a fire. Bending, distorting or deforming of these interior panels can result in significant problems in attempting to maintain a complete thermal insulation and seal within the safing slots between the outer edges of the floor construction and the exterior curtain wall construction during a storm or fire. In particular, maintaining of a complete thermal insulation and seal at all time during a fire is important to prevent heat, smoke and flames from spreading from one floor to an adjacent floor.
Curtain walls are general used and applied in modern building constructions and are the outer covering of said constructions in which the outer walls are non-structural, but merely keep the weather out and the occupants in. Curtain walls are usually made of a lightweight material, reducing construction costs. The wall transfers horizontal wind loads that are incident upon it to the main building structure through connections at floors or columns of the building. Curtain walls are designed to resist air and water infiltration, sway induced by wind and seismic forces acting on the building, and its own dead load weight forces. Curtain walls differ from store-front systems in that they are designed to span multiple floors, and take into consideration design requirements such as thermal expansion and contraction, building sway and movement, water diversion, and thermal efficiency for cost-effective heating, cooling, and lighting in the building.
A curtain wall structure is defined by an interior wall surface, which includes an interior panel, such as a back pan, extending over the interior surface thereof and at least one floor spatially disposed from the inner wall surface. The gap between the floor and the back pan of a curtain wall defines a safing slot, also referred to as perimeter slab edge, extending between the interior wall surface of the interior panel and the outer edge of the floor. This safing slot is essential to slow the passage of fire and combustion gases between floors. Therefore, it is of great importance to improve firestopping at the safing slot in order to keep heat, smoke and flames from spreading from one floor to an adjacent floor. It is important to note that the firestop at the perimeter slab edge is considered a continuation of the fire-resistance rating of the floor slab. The curtain wall itself, however, is not ordinarily required to have a rating.
Various designs have been known for curtain wall constructions and for means for thermally insulating and sealing the safing slot. For example, U.S. Pat. No. 7,856,775 B2 describes a thermal insulating and sealing means for a safing slot, wherein a supplementary insulation of thermally resistant material is attached to the interior panel of the wall at a position immediately below a primary insulation located between the interior panel and the floor, i.e. in the safing slot. Nevertheless, this employment has several drawbacks, such as that access is needed from the top and bottom to install said firestop system as well as the specific arrangement of the firestop system results in a limitation of joint width. Further, for example, perimeter fire-containment system CW-S-0002 from Specified Technology Inc. employs nom 4 pcf (64 kg/m3) density mineral wool batt insulation, which sections are cut to a width equal to the thickness of the floor and stacked to a thickness which is min. 50% greater than the width of the linear gap between the curtain wall insulation and the edge of the concrete floor slab, thereby being restricted in their application size. A min of 8 in. wide strips are needed in order to install the system properly resulting in a limitation of the system to the spandrel height, which is defined by the slab and strips thickness.
Therefore, there is a need for systems that can be easily installed within a safing slot, where, for example, access is only needed from one side, implementing a one-sided application. Further, there is a need for systems that are not limited to the width of a joint of a curtain wall structure. Additionally, maintaining safing insulation between the floors of a residential or commercial building and the exterior curtain wall responsive to various conditions including fire exposure should be guaranteed.
In view of the above, it is an object of the present invention to provide a thermal insulating and sealing means for thermally insulation and sealing of a safing slot in a building containing a curtain wall structure. In particular, it is an object of the present invention to provide a thermal insulating and sealing means which can be installed from one side, which maintains the safing insulation between the floors of a residential or commercial building and the exterior curtain wall responsive to various conditions, including fire exposure, and to maximize safing insulation at a minimal cost. Moreover, it is an object to provide a thermal insulating and sealing means which has no limitation of vertical movement capacities as well as limitation to spandrel height.
Further, it is an object of the present invention to provide a building construction comprising such a thermal insulating and sealing means for effectively thermally insulating and sealing of the safing slot between a curtain wall structure and the edge of a floor.
These and other objectives as they will become apparent from the ensuring description of the invention are solved by the present invention as described in the independent claims. The dependent claims pertain to preferred embodiments.
In one aspect, the present invention provides a thermal insulating and sealing means for effectively thermally insulating and sealing of a safing slot within a building construction having a wall construction defining an interior wall surface, which includes an interior panel extending over the interior surface thereof and at least one floor spatially disposed from the inner wall surface defining the safing slot extending between the interior wall surface of the interior panel and an outer edge of the floor, comprising a primary insulation means of thermally resistant material positioned in the safing slot, wherein the primary insulation means includes an inner primary end surface positionable in abutment with respect to the outer edge of the floor for sealing thereadjacent, an outer primary end surface positionable in abutment with respect to the interior panel, an upper primary facing surface extending between the inner primary end surface and the outer primary end surface and facing upwardly therebetween, a supplemental insulation means of thermally resistant material attached to the interior panel of a wall at a position immediately above the primary insulation means and in abutment with respect to the upper primary facing surface thereof, and a supplemental attachment means for attaching of the supplemental insulation means with respect to the interior panel positioned thereadjacent.
In another aspect, the present invention provides a building construction comprising said thermal insulating and sealing means.